ReactNative前端与原生事件交互----弹出Android的Toast

一、点击页面按钮，弹出Android的Toast

第一步：创建MyNativeModule

public class MyNativeModule extends ReactContextBaseJavaModule {
    private Context mContext;
    public MyNativeModule(ReactApplicationContext reactContext) {
        super(reactContext);
        mContext = reactContext;
    }

    @Override
    public String getName() {
        return "MyNativeModule";
    }
    @ReactMethod
    public void rnCallNative(String msg){

        Toast.makeText(mContext,msg,Toast.LENGTH_SHORT).show();

    }

}

第二步：创建MyReactPackage

public class MyReactPackage implements ReactPackage{
    @Override
    public List createNativeModules(ReactApplicationContext reactContext) {
        List modules=new ArrayList<>();
        //将我们创建的类添加进原生模块列表中  
        modules.add(new MyNativeModule(reactContext));
        return modules;
    }

    @Override
    public List> createJSModules() {
        //返回值需要修改  
        return Collections.emptyList();
    }

    @Override
    public List createViewManagers(ReactApplicationContext reactContext) {
        return Collections.emptyList();
    }
}

第三步：添加包管理文件

 @Override
    protected List getPackages() {
      return Arrays.asList(
          new MainReactPackage(),
              new MyReactPackage()
      );
    }

第四步：index.android.js中处理

   render() {
        return (
            

              
                React Native 调用原生方法!
              

              
                To get started, edit index.android.js
              

              
                Double tap R on your keyboard to reload,{'\n'}
                Shake or press menu button for dev menu
              

            
        );
    }

    call_button(){

        NativeModules.MyNativeModule.rnCallNative('调用原生方法的Demo');
    }